Image colors change when pasted into Word

[Eric]

I have written a C# program that creates a new bitmap:

Bitmap ChartBitmap = new Bitmap( 780, 360 );

then I create a button which copies that bitmap into the clipboard:

Clipboard.SetDataObject( ChartBitmap );

after which I paste that bitmap into MS Word. Some of the colors
change or don't show up when the bitmap is pasted into Word. This
happens in Windows 2000 in Word 97. Some colors seem to work, like
blue, and others, like lavender don't. I suppose this has something to
do with the default pallete in Word.

How can I create my my bitmap so that it will retain the colors and
paste them correctly into Word?

Thanks in advance

Eric